各類從句講解

1、各類從句講解各類從句詳解英語從句可以分為名詞性從句、定語從句和狀語從句三大類：下面我們逐一進(jìn)行說明：一、名詞性從句（主語從句、表語從句、賓語從句、同位語從句） 主語從句、表語從句、賓語從句和同位語從句在復(fù)合句中的充當(dāng)?shù)某煞趾推涿Q相同，分別作主句的主語、表語、賓語和同位語。上述這四種從句均被稱為名詞性從句。所有的名詞性從句均不能用逗號(hào)分開，并且它們都用相同的關(guān)聯(lián)詞，關(guān)聯(lián)詞如下： 主從連詞：that (無意義), whether (是否), if (是否)（在句子中不充當(dāng)任何成分） 連接代詞：who (誰), whom (誰), whose (誰的), what (什么), which (哪一個(gè)

2、) 連接副詞：when (什么時(shí)候), where (什么地方), how (怎樣), why (為什么)主從連詞只起連接作用，連接代詞和連接副詞除了起連接作用外，還充當(dāng)從句某一個(gè)成分。另外，可以用whatever, whichever, whoever, who(m)ever等連接代詞引導(dǎo)名詞性從句，來加強(qiáng)語氣。下面分別對(duì)各種名詞性從句進(jìn)行介紹（一）主語從句（subject clause）在主句中用作主語的主謂結(jié)構(gòu)稱之為主語從句。例如： That he will come to the discussion is certain.他來參加討論是確定的。 That the moon moves

3、 round the earth is well known to all of us.月球繞地球轉(zhuǎn)動(dòng)，這是我們大家都熟知的。 When the meeting is to be held has not yet been decide. 會(huì)議什么時(shí)候召開還沒有決定。主語從句放在句首，句子常常顯得比較笨重，因此通?？梢园裪t放在句首，作形式主語，而將主語從句放在后面。例如上面的句子可以分別改寫為：It is certain that he will come to the discussion.It is well known to all of us that the moon moves

4、round the earth.It has not yet been decide when the meeting is to be held.下面再舉一些例句：What they are after is profit.他們追求的是利潤。That he is still alive is sheer luck.他還活著全靠運(yùn)氣。Who did the work is unknown.誰干了這工作無人知道。Whether she will join us wont make too much difference.It wont make too much difference wheth

5、er she will join us. 她是否參與我們的活動(dòng)無關(guān)緊要。Which way is more effective is still a question.It is still a question which way is more effective. 哪種辦法效率更高還是個(gè)問題。（二）表語從句（predicative clause）在主句中擔(dān)當(dāng)表語的主謂結(jié)構(gòu)稱之為表語從句。One idea is that fish is the best brain food.有一種看法認(rèn)為魚是最好的補(bǔ)腦食品。The problem is where we can hold our mee

6、ting.問題是我們可以在哪兒舉行會(huì)議。My question is how information is stored in the long-term memory.我的問題是信息是怎樣儲(chǔ)存在長期記憶中的。That is what he really wants.那就是他真想要的東西。It seems that everything goes smoothly.似乎一切都進(jìn)行得很順利。（三）賓語從句（object clause）在主句中作謂語動(dòng)詞、介詞及非謂語動(dòng)詞的賓語的主謂結(jié)構(gòu)稱之為賓語從句。在引導(dǎo)賓語從句時(shí)，從屬連詞that在口語中和非正式文本中常省略。（1）動(dòng)詞后的賓語從句We kn

7、ow that a parrot cant really speak.我們知道鸚鵡不會(huì)真的說話。He wants to tell us what he thinks.他想告訴我們他所想的事情。Knowing that it was going to rain, they decided to work inside the house.知道要下雨了，于是他們決定在室內(nèi)工作。(現(xiàn)在分詞knowing的賓語從句)I want to know whether/if you still work in the factory.我想知道你是否還在工廠工作。（不定式to know的賓語從句）The clu

8、b will give whoever wins a prize. 獲勝者俱樂部將頒獎(jiǎng)。Up to now we cant say whether his theory can stand the test.到目前為止我們還不能說他的理論是否經(jīng)得住考驗(yàn)。A little observation will show how the temperature changes.稍加觀察就可以看出溫度是怎樣變化的。Do you know who lives in this room?你知道誰住在這房間里嗎？（2） 介詞后的賓語從句He laughed at what they said. 她對(duì)他們說的話

9、一笑置之。There is disagreement among economists about what money is and how money is measured.什么是貨幣以及怎樣計(jì)量貨幣在經(jīng)濟(jì)學(xué)家之間存在分歧。（3）形容詞的賓語從句有些形容詞可以用that引導(dǎo)賓語從句，表示說話人對(duì)某一事物的態(tài)度并帶有感情色彩。常見的這類形容詞有：afraid, amazed, astonished, aware, certain, confident, delighted, glad, grateful, happy, proud, sad, sorry, sure, surprised等

10、。 “害怕，驚訝，震驚，意識(shí)，確定，自信，高興，高興，高興，高興，自豪，傷心，對(duì)不起，當(dāng)然，驚訝”例如：I am glad that you have come. 你來了，我真高興。I am afraid that you are wrong on this point.恐怕你在這點(diǎn)上是錯(cuò)誤的。He is quite confident that he will pass the examination.他很有信心通過這個(gè)考試。（四）同位詞從句（apposition clause）同位語從句就是在句子中擔(dān)當(dāng)同位語的主謂結(jié)構(gòu)。主句中有些詞義比較抽象的名詞，如：belief, doubt, evi

11、dence證據(jù), idea, fact, hope, news, possibility, question, thought等，可以用that、連接代詞和連接副詞引出同位語從句。There is no doubt that a large number of people benefit from heart surgery.毫無疑問，有許多人得益于心臟外科手術(shù)。I have an idea that parents should monitor監(jiān)控the kind of television their children watch.我有一個(gè)想法，父母應(yīng)該檢查孩子看電視的內(nèi)容。There

12、is the news that some British customers will visit our company. 有消息說幾個(gè)英國客戶要來我公司參觀。Is there any proof that the food of the plant differs from that of animals?是否有任何證據(jù)可以說明植物性的食物不同于動(dòng)物性的食物呢？We all know the fact that organization helps memorization.我們都知道這樣一個(gè)事實(shí)：把要記憶的材料組織起來有助于記憶。注意：雖然that在同位語從句中沒有什么意義，但不能省略

13、。區(qū)別：盡管由that引導(dǎo)的同位語從句與that引導(dǎo)的定語從句很相似，但兩者有明顯的區(qū)別。 (a) that在同位語從句中是連詞，只起連接作用，無具體詞義，不能在從句中充當(dāng)成分；而用that引導(dǎo)的定語從句中，that是關(guān)系代詞，在從句中充當(dāng)一定成分，并有詞意。 (b) 同位語從句與其先行詞在邏輯上有“主系表”的關(guān)系，例如上面的第一句可以理解為：“許多人得益于心臟外科手術(shù)是毫無疑問的”上述其它各句也是如此，而定語從句則沒有這種關(guān)系。（五）只可用whether但不可用if的情況if, whether引導(dǎo)的名詞性從句表示“是否”，其異同點(diǎn)如下：相同點(diǎn)： (a) 用作賓語從句時(shí)，它們可互相替換。例如：

14、I wonder if/whether you can help me.我想知道你是否能幫助我。 (b) 都可與or連用。例如：Please tell me if/whether they are Swedish or Danish. 訴我他們是瑞典人還是丹麥人。不同點(diǎn)：（只可用whether但不可用if的情況） (a) if不能用于在句首的主語從句。例如：Whether John will go remains a question. 約翰是否去還是一個(gè)問題。Whether she likes the present is not clear to me. 她是否喜歡禮物我還不清楚。但可以說

15、Its not clear to me if/whether she likes the present. （因?yàn)闆]有在句首，所以可以用if） (b) if不能用于表語從句The point is whether we should lend him the money. 問題在于我們是否應(yīng)該借錢給他。 (c) if不能引導(dǎo)介詞的賓語從句I worry about whether he can pass through the crisis of his illness.我擔(dān)心他是否能度過疾病的危險(xiǎn)期。 (d) if不能引導(dǎo)同位語從句They are investigating the que

16、stion whether the man is trustworthy.他們調(diào)查他是否值得信賴。 (e) if后不能接or notI dont care whether you like the plan or not. 我不在乎你是否喜歡該計(jì)劃。是用if還是用whether是一個(gè)考點(diǎn)，但能用if的場合一定能用whether，反之則不然。 二、定語從句在復(fù)合句中修飾名詞或代詞的從句是定語從句（attributive clause）被定語從句修飾的詞叫先行詞，定語從句必須放在先行詞后面。定語從句一般由關(guān)系代詞：that, which, who, whom, whose和關(guān)系副詞：when, w

17、here, why引出。注意區(qū)別：在名詞性從句中，that是連詞，在句中不充當(dāng)任何成分，且沒有任何意義；而在定語從句中，that是關(guān)系代詞，在句中充當(dāng)一定成分，并有詞意。（一）由關(guān)系代詞引出的定語從句關(guān)系代詞which指物，在從句中作主語或賓語；who指人，在從句中作主語或賓語；whom指人，在從句中作賓語；that指人或物，常用于替代which, who, whom，在從句中作主語或賓語。whose指人或物，在從句中作定語。例如：1. There are many sounds which/that have a meaning and yet are not words.有許多聲音有意義但

18、不是詞。（which/that在從句中作主語）2. The few points which/that the president stressed in his report are very important indeed.校長在報(bào)告中強(qiáng)調(diào)的幾點(diǎn)確實(shí)非常重要。（which/that在從句中作賓語）3. Some people who/that are successful language learners often fail in other fields.有些在語言學(xué)習(xí)上很成功的人，在其他領(lǐng)域常常一無所成。（who/that在從句中作主語）4. Here is the man wh

19、om/who/that youve been looking for.這就是你一直在找的人。（whom/who/that在從句中作賓語）5. She lives in the house whose door and windows are broken.她住在門窗已經(jīng)壞了的房子里。（whose指物，在從句中作定語）6. How many students are there in your class whose parents serve in the government agencies?你們班里有多少同學(xué)的父母在政府機(jī)關(guān)工作。（whose指人，在從句中作定語）注意，在定語從句中的關(guān)系

20、代詞which, who, whom, that等，如果在從句中作賓語，也可以省略。例如上面的第二句、第四句也可以改為：The few points the president stressed in his report are very important indeed.Here is the man youve been looking for.介詞提前在從句中，如果which或whom在定語從句中原為介詞的賓語，那么這個(gè)介詞可以提到從句之前。（但that, who不適用）例如：The girl to whom you spoke is my sister. （The girl whom

21、 you spoke to is my sister.）跟你說話的那個(gè)女孩是我妹妹。前面說過，在定語從句中，如果關(guān)系代詞做賓語可以省略，但是如果是介詞的賓語，則關(guān)系代詞省略后，介詞不能提前，例如上句可改寫為：The girl you spoke to is my sister.（如果關(guān)系代詞省略，to不能提前了）（二）關(guān)系副詞引出的定語從句關(guān)系副詞when（指時(shí)間），where（指地點(diǎn)），why（指原因）等引出的定語從句分別用來修飾表示時(shí)間、地點(diǎn)、原因的先行詞。這些關(guān)系副詞在從句中均作狀語。例如：1. At the time when I saw him, he was well.在我看到他的

22、時(shí)候，他身體很好。2. This is the place where the accident took place last night.這就是昨晚發(fā)生事故的地方。3. That is the reason why I am not in favor of your plan.這就是我不贊成你的計(jì)劃的原因?？梢杂媒樵~which結(jié)構(gòu)替換關(guān)系副詞。其中：when at/in/on/during which 表示時(shí)間where in/at which 表示地點(diǎn)why for which 表示原因1. Do you remember the day when/on which you joined

23、 our club?還記得你加入我們俱樂部的那一天嗎？2. He will always remember the day when/on which his father returned from America.他將永遠(yuǎn)記住父親從美國返回的那一天。3. This was the time when/at which she left for Beijing.這就是她動(dòng)身去北京的時(shí)間。4. This is the house where/in which I lived two years ago.這是我兩年前住過的房子。5. I dont know the reason why/for

24、which he didnt come to the meeting yesterday morning.我不知道他為什么沒參加昨天上午的會(huì)議。（三）限制性定語從句和非限制性定語從句 定語從句根據(jù)與先行詞的密切程度可分為限制性定語從句和非限制性定語從句。限制性定語從句限制性定語從句與先行詞關(guān)系密切，從句是整個(gè)句子不可缺少的部分，如果去掉它，句子的意思就不完整或不明確。從句與主句之間不用逗號(hào)隔開。譯成漢語時(shí)，一般先譯定語從句，再譯先行詞。1. The distance that light travels in one second is 300thousand kilometers.光在一秒鐘

25、所走的距離為30萬公里。2. Those who want to go please sign their names here.想去的人在這里簽名。3. This is the place where the Anti-Japanese War broke out.這里是抗日戰(zhàn)爭爆發(fā)的地方。此外，前面所給出的例句均為限制性定語從句。非限制性定語從句非限制性定語從句與先行詞的關(guān)系比較松散，從句只是對(duì)先行詞的附加說明。如果去掉它，句子的意思仍然清楚。從句與主句之間常用逗號(hào)隔開。譯成漢語時(shí)，從句常單獨(dú)譯成一句。例如：1. Steel, which has many useful propertie

26、s, is widely used in the machine-building industry.鋼有許多有用的特性，所以它在機(jī)械制造業(yè)中得到了廣泛的應(yīng)用。2. Mr. Brown, who just came from Britain yesterday, will teach us accounting this term.布朗先生昨天剛從英國來，這學(xué)期將教我們會(huì)計(jì)學(xué)。3. She is going to spend the winter holidays in Hainan, where she has some relatives.她準(zhǔn)備到海南度寒假，那兒她有一些親戚。（四）as引

27、出的定語從句as常在suchas和sameas的結(jié)構(gòu)中作關(guān)系代詞，引出定語從句。例如：1. Such people as you describe are rare nowadays.你描述的這種人現(xiàn)在已經(jīng)寥寥無幾了。2. Let us discuss only such question as concern everyone of us.我們只討論與我們每個(gè)人有關(guān)的問題吧。3. I feel just the same as you do.我的感覺和你一樣。4. My stand on this problem is just the same as it was four years a

28、go.在這個(gè)問題上，我的立場和四年前一樣。（五）關(guān)系代詞that與which的比較在定語從句中，當(dāng)先行詞是物時(shí)，引導(dǎo)詞that和which常常可以通用，但以下幾種情況需注意。注意1只宜于用which，不用that的情況。(1)先行詞為that，those時(shí)。Whats that which is under the desk? 在桌子底下的那個(gè)是什么？(2)引導(dǎo)詞（關(guān)系代詞）前有介詞時(shí)。This is the room in which he lives. 這是他居住的房間。注意2只宜于用that，不用which的情況。(1)先行詞是形容詞最高級(jí)或者它的前面有形容詞最高級(jí)修飾時(shí)。The fil

29、m is the most interesting that I have ever seen. 這部電影是我看過的最有趣的一部。English is the most difficult subject that you will learn during these years. 英語會(huì)是這些年你學(xué)的最難的科目。(2)先行詞是序數(shù)詞或它的前面有l(wèi)ast或序數(shù)詞修飾時(shí)。Its the first film that I saw this year. 這是我今年看的第一部電影。Tom is always the first that comes to the classroom. Tom總是第

30、一個(gè)到教室的人。(3)主句以疑問詞who，which開頭時(shí)，不用which或who，以避免重復(fù)。Which is the bike that you lost? 哪輛是你丟的自行車？(4)先行詞既有人又有物時(shí)。They are taiking about the sutdents and the school that they visited yesterday. 他們正在談?wù)撟蛱煸L問的學(xué)生和學(xué)校。(5)先行詞是all, much, little, something, everything, anything, nothing, none, the one等代詞時(shí)。You should h

31、and in all that you have. 你應(yīng)該把你有的所有上交。We havent got much that we can offer you. 我們沒有太多能提供給你。Is this school the one that we are going to visit tomorrow? 這所學(xué)校是我們明天要參觀的那個(gè)嗎？Is there anything that you want to buy? 你有什么想要買的東西嗎？(6) 先行詞前有no, any, few, little, all, the only, the same, the very等詞修飾時(shí)。The only

32、thing that we can do is to give you some money. 我們能做的唯一的事就是給你一些錢。There are no children that dont love their parents. 沒有孩子不愛他們的父母。三、狀語從句在復(fù)合句中起狀語作用的從句叫狀語從句（adverbial clause）。狀語從句按其意義可以分為：時(shí)間、地點(diǎn)、原因、目的、結(jié)果、條件、比較、方式、讓步等類別。下面就按狀語從句的類別逐一介紹。 （一）時(shí)間狀語從句時(shí)間狀語從句通常由下列連詞引導(dǎo)：when, whenever, as, while, since, till, unt

33、il, before, after, once, as soon as, no sooner than, hardly when, scarcely when等例如：I will discuss this with you when we meet.我們見面時(shí)再與你討論這件事。Come and see me whenever you want to.任何時(shí)候想來就來看看我。We must strike while the iron is hot.我們必須趁熱打鐵。As he was making his experiments, he observed this physical phenom

34、enon.當(dāng)他在做實(shí)驗(yàn)時(shí)，他觀察到這個(gè)物理現(xiàn)象。I watched her until she disappeared from sight in the distance.我看著她直到她遠(yuǎn)遠(yuǎn)地消失在視野中。You havent changed much since we met last year.自從去年我們見面以來，你變化不大。He had learned English for three years before he went to London.他去倫敦之前已學(xué)了三年英語。The sun came out soon after the storm stopped.暴風(fēng)雨過后不久，

35、太陽出來了。Ill send you the sample as soon as it is made ready.一旦樣品制好，我馬上給你寄去。注意：when, as, while的區(qū)別區(qū)別1: when, as, while都可以表示一段持續(xù)性時(shí)間，但表示一個(gè)時(shí)間點(diǎn)時(shí)，要用when, as而不能用while。例如：He entered the room when/as/while the meeting was going on.正當(dāng)開會(huì)的時(shí)候他走進(jìn)了房間。（開會(huì)是一個(gè)持續(xù)性時(shí)間）但是：When/as he finished the speech, the audience burst i

36、nto applause.當(dāng)他講話結(jié)束時(shí)，聽從掌聲雷動(dòng)。（講話結(jié)束是一個(gè)時(shí)間點(diǎn)，不能用while）區(qū)別2：when除有“當(dāng)?shù)臅r(shí)候”之意外，還有“當(dāng)之后，然后”之意，因此從句的動(dòng)作發(fā)生在主句動(dòng)作之前，只能用when 引導(dǎo)從句，不可用as 或 while。例如：When you have finished your work, you may have a rest.當(dāng)你干完活后，你可以休息一下。（從句動(dòng)作在主句前，只能用when） 此外，時(shí)間狀語從句還可以由一些名詞引導(dǎo)，如：the moment, the instant, the minute, the second, the day, eve

37、ry time等。此外有些副詞也可以引導(dǎo)時(shí)間狀語從句，如：instantly, directly, immediately等。例如：Ill telephone you the instant I know.我一知道就立即給你打電話。Every time I catch a cold, my nose runs.我一感冒就流鼻涕。I came immediately Id eaten.我一吃完飯就來了。 （二）地點(diǎn)狀語從句地點(diǎn)狀語從句主要由：where, wherever引導(dǎo)。Where I live there are plenty of trees.我住的地方樹很多。You have the

38、 right to live where you want.你有權(quán)居住在你想住的地方。Wherever I am I will be thinking of you.不管我在哪里我都會(huì)想到你。 Sit wherever you like.你想坐在哪里就坐在那里。Wherever you go you will see great changes that have taken place in that city.不管你走到哪里，你都會(huì)看到那座城市發(fā)生的巨大變化。 （三）原因狀語從句原因狀語從句經(jīng)常由下列連詞引導(dǎo)：because, as, since, for, in that, now (t

39、hat), seeing (that), considering (that), not thatbut that等。其中because通常放在主句后面（有時(shí)也可放在句首）；其語氣比as, since要強(qiáng)，在回答why引導(dǎo)的疑問句時(shí)，必須用because回答；since通常放在句首，常表示已為人們所知的原因或理由；語氣比because要弱；as可放在句首或句末，語氣相對(duì)更弱；for不能用于句首，只能用于主句后，for引導(dǎo)的從句并不說明主句行為發(fā)生的直接原因，只是一種解釋，語氣要比because弱得多。例如：She has just missed her bus because the time

40、table has changed.因?yàn)槠嚂r(shí)刻表變了，她沒有趕上汽車。As the weather was fine, we decided to climb the mountain.因?yàn)樘鞖夂芎?，我們決定爬山。Since he is busy, I wont trouble him.既然他很忙，我就不打擾他了。He felt no fear, for he was very brave.他沒有感到恐懼，因?yàn)樗苡赂摇?for不能用在句首)in that, now (that), seeing (that), considering (that)這幾個(gè)連詞與as, since的意義相近，都

41、有“鑒于某種事實(shí)，原因是”的意思，例如：A gas differs from a solid in that it has no definite shape.氣體不同于固體就在于它沒有一定的形狀。Now that all are present, lets start the discussion.既然全都出席了，我們就開始討論。Seeing (that) she was seriously ill, they sent for the doctor.鑒于她病情嚴(yán)重，他們派人請了醫(yī)生。not thatbut that表示：“不是(因?yàn)?，而是(因?yàn)?”。He left a bit worri

42、ed, not that his students were not working hard, but that they cared little for their health.他有些著急，不是因?yàn)樗膶W(xué)生不努力學(xué)習(xí)，而是因?yàn)樗麄儾惶⒁馍眢w健康。注意：原因狀語從句與結(jié)果狀語從句?？苫Q：例如：John flew into a rage because I took no notice of him.因?yàn)槲覜]有注意到約翰，他生氣了。I took no notice of John, so that he flew into a rage.我沒有注意到約翰，結(jié)果他生氣了。上面可以看出，原

43、來的原因狀語從句變?yōu)榱酥骶?，而原來的主句變?yōu)榱私Y(jié)果狀語從句。 （四）目的狀語從句目的狀語從句通常由that, so that, in order that, lest, for fear that等引導(dǎo)例如：They set out early that they might arrive at the station in good time.他們很早就出發(fā)了，以便及時(shí)趕到車站。Lets take the front seats so that we can see more clearly.我們坐前排吧，這樣可以看得更清楚一些。We should do our utmost in orde

44、r that we may be able to over fulfill the task.為了超額完成任務(wù)，我們應(yīng)該全力以赴。He took his umbrella with him lest it rain.他帶了雨傘，以防下雨。Batteries must be kept in dry places for fear that electricity leak away.電池一定要放在干燥的地方，以免漏電。注意有時(shí)目的狀語從句要用虛擬語氣，例句請參考有關(guān)“虛擬語氣”的章節(jié)。 （五）結(jié)果狀語從句結(jié)果狀語從句通常由：so that, sothat, suchthat等引導(dǎo)。例如：He m

45、ade a wrong decision, so that half of his lifetime was wasted.他作了錯(cuò)誤的決定，結(jié)果毀掉了半生。The problem is so complicated that it will take us much time to work it out.這道題這么復(fù)雜，我們要用很多時(shí)間才能解決。The mountain is so high that she cant climb it up to the top.那座山太高了，她無法登上山頂。He ran so fast that his brother couldnt catch up

46、 with him.他跑得太快了，他弟弟趕不上他。The aircraft was flying at such a high altitude that we could hardly see it.飛機(jī)飛行的高度是這么的高，以致于我們幾乎看不到它。He is such a naughty boy that he becomes unwelcome in his neighborhood.他是那么個(gè)調(diào)皮的孩子，以至在鄰里中不受歡迎。 （六）條件狀語從句條件狀語從句可由下列連詞引導(dǎo)：if, unless, on condition (that), suppose/supposing (that

47、), provided/providing (that), as/so long as, in case等。If it snows tomorrow, we will build a snowman.明天如果下雪，我們就堆雪人。If you are not too tied, lets go out for a walk.如果你不太累，我們?nèi)ド⑸⒉?。Youll be late unless you hurry.如果不趕快的話，你會(huì)遲到的。（ unless ifnot ）Ill lend you my computer on condition (that) you keep it in goo

48、d shape.如果你能保持我的計(jì)算機(jī)的良好狀態(tài)，我就可以借給你用。Suppose we are late, what will he say?假如我們遲到，他會(huì)說什么？Supposing we cant get the necessary data, what shall we do?假如我們弄不到必要的數(shù)據(jù)，那我們怎么辦呢？Providing you promise not to tell anyone else, Ill explain the secret.只要你保證不告訴任何人，我就把這個(gè)秘密講給你聽。In case it rains, do not expect me.萬一下雨，就

49、不要等我了。He will do anything as long as it is interesting.只要有意義，他什么都愿意干。有些條件狀語從句可以或必須使用虛擬語氣，詳見“虛擬語氣”。 （七）比較狀語從句比較狀語從句可由下列連詞引導(dǎo)：than, asas, not so/asas, thethe等。Bill is taller than Bob (is).比爾比鮑勃高。I can walk faster than you can run.我走得比你跑得還要快。He is a greater painter than people suppose (he is).他是一個(gè)比人們想像的更偉大的畫家。Tom works as hard as John (dose).湯姆和約翰工作一樣努力。Her mother is not as tall as she (is).她媽媽沒有她高.注意：than, asas從句與主句結(jié)構(gòu)上相同的部分常省略，只